CSCI {4,6}900: Ubiquitous Computing Announcements 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

CSCI {4,6}900: Ubiquitous Computing Outline Overview of IP (continued) IPv6 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

CSCI {4,6}900: Ubiquitous Computing Addressing The McGraw-Hill Companies, Inc., 2000 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

CSCI {4,6}900: Ubiquitous Computing OSI in IP world The McGraw-Hill Companies, Inc., 2000 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

User Datagram Protocol (UDP) Simple demultiplexing No guarantees about reliability, in-order delivery Thin veneer on top of IP adds src/dest port numbers 16 bit port number allows for identification of 65536 unique communication endpoints per host Note that a single process can utilize multiple ports IP addr + port number uniquely identifies all Internet endpoints 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

User Datagram Protocol (UDP) The McGraw-Hill Companies, Inc., 2000 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

Transmission Control Protocol (tcp) Reliable in-order delivery of byte stream Full duplex (endpoints simultaneously send/receive) e.g., single socket for web browser talking to web server Flow-control To ensure that sender does not overrun receiver Fast server talking to slow client Congestion control Keep the sender from overrunning the network Many simultaneous connections across routers (cross traffic) 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

CSCI {4,6}900: Ubiquitous Computing TCP headers 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

CSCI {4,6}900: Ubiquitous Computing IPv6 Large Address space - 128 bit addresses Every toaster can have its own IP address Aggregation-based address hierarchy Efficient backbone routing Efficient and Extensible IP datagram No fragmentation by routers 64 bits field alignment Simpler basic header Auto-configuration Security IP Renumbering part of the protocol 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

CSCI {4,6}900: Ubiquitous Computing IPv6 address space 128 bits = 3.4 E 38 addresses Imagine Bill Gates’ fortune is 85 billions $ (8.5 E 10) Take 1 trillion Bill Gates’es Convert their fortune to pennies Assign 1 E 12 addresses to each pennies Takes 8.5 E 36 addresses – You’ve just assigned 2.5% of the entire IPv6 address space http://www.cnn.com/TECH/computing/9909/21/ip.crunch.idg/index.html 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

IPv6 address representation Format is x:x:x:x:x:x:x:x x is a 16 bit hexadecimal field FEDC:BA98:7654:3210:FEDC:BA98:7654:3210 Leading zeros in a field are optional :: can be used to represent multiple groups of 16 bits of zero :: can only be used once in an address FF01:0:0:0:0:0:0:101 = FF01::101 0:0:0:0:0:0:0:1 = ::1 0:0:0:0:0:0:0:0 = :: Preferred Format for Literal IPv6 Addresses in URL http://[1080::8:800:200C:417A]:80/index.html 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

Global unicast address 3FFE:0B00:0C18:0001:0290:27FF:FE17:FC0F 16 bits 32 bits 16 bits 64 bits TLA – top level aggregator Primary providers NLA: Next Level Aggregator Can have multiple NLA as sub-NLA SLA: Site Level Aggregator Your site (16 bits) Addresses are allocated from your provider If you change provider, your prefix changes But renumbering (of hosts, routers and sites) has been included in the IPv6 protocol TLA NLA(s) SLA Interface ID 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

CSCI {4,6}900: Ubiquitous Computing Anycast Address assigned to more than one interface and/or node Packet sent to anycast address is routed to “closest” interface Server1 Server2 Servern Router 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

CSCI {4,6}900: Ubiquitous Computing IPsec Provides authentication (AH) and confidentiality (ESP) at the IP level Mandatory in IPv6 IPv6 Next Header defines IPsec AH and ESP 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

CSCI {4,6}900: Ubiquitous Computing Mobility Mobility Allows a mobile node to keep the same IP address Integrated in IPv6 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

CSCI {4,6}900: Ubiquitous Computing Transition Dual stack host Node has both IPv4 and IPv6 stacks and addresses DNS resolver returns IPv6, IPv4 or both to application IPv6 application can use IPv4 mapped addresses to communicate with IPv4 nodes Tunneling Encapsulate IPv6 packet within a IPv4 packet while traversing IPv4 network. Configured Tunneling Automatic Tunneling IPv4-compatible IPv6 addresses IPv4 multicast tunneling 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

CSCI {4,6}900: Ubiquitous Computing Discussion 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing

CSCI {4,6}900: Ubiquitous Computing 30-Nov-18 CSCI {4,6}900: Ubiquitous Computing